As electric vehicle (EV) technology matures, the need for compact and efficient power electronics will continue to grow. To increase power density and efficiency, it is ideal to minimize the size and power loss of com...
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Refractory high-entropy alloys(RHEAs)exhibit outstanding strength at room temperature,but their high-temperature applications are hindered by severe ***,we report slip-band-driven dy-namic recrystallization to enhance...
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Refractory high-entropy alloys(RHEAs)exhibit outstanding strength at room temperature,but their high-temperature applications are hindered by severe ***,we report slip-band-driven dy-namic recrystallization to enhance the high-temperature strain hardening of HfNbTaTiZr *** intro-ducing partial lattice defects through hot forging,we increase the nucleation sites for dynamic recrys-tallization during subsequent thermomechanical deformation,thus suppressing the strain-softening *** reveal that the high-temperature deformation is governed by the formation of heterogeneous bimodal grains along slip bands,which effectively constrain dislocation motion and improve strength,while microbands prevent premature *** fracture mode also changes from ductile to mixed to cleavage-dominated with increasing *** results demonstrate a simple and effective method for overcoming high-temperature strain-softening for BCC high entropy alloys.
Hydrogen embrittlement in Al-Zn-Mg-Cu alloys is suggested to originate from debonding of the η phase interface. Previous studies have shown that intragranular T phase precipitation, facilitated by increased Mg conten...
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As a catalyst of the air cathode in zinc-air batteries,tungstic acid ferrous(FeWO_(4)),a nanoscale transition metal tungstate,shows a broad application prospect in the oxygen reduction reaction(ORR).While FeWO_(4)poss...
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As a catalyst of the air cathode in zinc-air batteries,tungstic acid ferrous(FeWO_(4)),a nanoscale transition metal tungstate,shows a broad application prospect in the oxygen reduction reaction(ORR).While FeWO_(4)possesses favorable electrochemical properties and thermodynamic stability,its intrinsic semiconductor characteristics result in a relatively slow electron transfer rate,limiting the ORR catalytic *** this work,the electronic structure of FeWO_(4)is significantly modulated by introducing phosphorus(P)atoms with abundant valence *** P doping can adjust the electronic structure of FeWO_(4)and then optimize oxygen-containing intermediates'absorption/desorption efficiency to achieve improved ORR ***,the sodium chloride template is utilized to construct a porous carbon framework for anchoring phosphorus-doped iron tungstate(P-FeWO_(4)/PNC).The porous carbon skeleton provides numerous active sites for the absorption/desorption and redox reactions on the P-FeWO_(4)/PNC surface and serves as mass transport channels for reactants and *** P-FeWO_(4)/PNC demonstrates ORR performance(E1/2=0.86 V ***).Furthermore,the zinc-air batteries incorporating the P-FeWO_(4)/PNC composite demonstrate an increased peak power density(172.2 mW·cm^(-2)),high specific capacity(810.1 mAh·g^(-1)),and sustained long-term cycling stability lasting up to 240 *** research not only contributes to the advancement of cost-effective tungsten-based non-precious metallic ORR catalysts,but also guides their utilization in zinc-air batteries.
Traditional linear vibration isolators struggle to combine high load-bearing capacity with low-frequency vibration isolation, whereas nonlinear metastructure isolators can effectively fulfill both functions. This pape...
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Traditional linear vibration isolators struggle to combine high load-bearing capacity with low-frequency vibration isolation, whereas nonlinear metastructure isolators can effectively fulfill both functions. This paper draws inspiration from the Quasi-Zero Stiffness (QZS) characteristics resulting from the buckling deformation of beams, and proposes a gear-based QZS structure by arranging beams in a circular array. We investigated the static mechanical behavior under different structural parameters, loading angles, and gear combinations through experiments and simulations, and demonstrated the mechanical performances could be effectively programmed. Subsequent vibration isolation tests on the double gears prove superior vibration isolation performance at low frequency while maintaining high load-bearing capacities. Additionally, a key contribution of our work is the development of a mathematical model to characterize the buckling behavior of the unit beam within the gear structure, with its accuracy validated through finite element analysis and experimental results. The gear’s modulus, number of teeth, and pressure angle are selected according to standard series, allowing the gear can be seamlessly integrated into existing mechanical systems in critical fields such as aerospace, military, and etc.
High-nickel ternary cathodes hold a great application prospect in solid-state lithium metal batteries to achieve high-energy density,but they still suffer from structural instability and detrimental side reactions wit...
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High-nickel ternary cathodes hold a great application prospect in solid-state lithium metal batteries to achieve high-energy density,but they still suffer from structural instability and detrimental side reactions with the solid-state *** circumvent these issues,a continuous uniform layer polyacrylonitrile(PAN)was introduced on the surface of LiNi_(0.8)Mn_(0.1)Co_(0.1)O_(2) via in situ polymerization of acrylonitrile(AN).Furthermore,the partial-cyclized treatment of PAN(cPAN)coating layer presents high ionic and electron conductivity,which can accelerate interfacial Li+and electron diffusion *** the thermodynamically stabilized cPAN coating layer cannot only effectively inhibit detrimental side reactions between cathode and solid-state electrolytes but also provide a homogeneous stress to simultaneously address the problems of bulk structural degradation,which contributes to the exceptional mechanical and electrochemical stabilities of the modified ***,the coordination bond interaction between the cPAN and NCM811 can suppress the migration of Ni to elevate the stability of the crystal *** from these,the In-cPAN-260@NCM811 shows excellent cycling performance with a retention of 86.8%after 300 cycles and superior rate *** endow the solid-state battery with thermal safety stability even at hightemperature extreme *** facile and scalable surface engineering represents significant progress in developing high-performance solid-state lithium metal batteries.
Designing refractory high-entropy alloys(RHEAs)for high-temperature(HT)applications is an outstanding challenge given the vast possible composition space,which contains billions of candidates,and the need to optimize ...
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Designing refractory high-entropy alloys(RHEAs)for high-temperature(HT)applications is an outstanding challenge given the vast possible composition space,which contains billions of candidates,and the need to optimize across multiple ***,we present an approach that accelerates the discovery of RHEA compositions with superior strength and ductility by integrating machine learning(ML),genetic search,cluster analysis,and experimental *** iteratively synthesize and characterize 24 predicted compositions after six feedback *** compositions show outstanding combinations of HT yield strength and room-temperature(RT)ductility spanning the ranges of 714–1061 MPa and 17.2%–50.0%fracture strain,*** identify an attractive alloy system,ZrNbMoHfTa,particularly the composition Zr_(0.13)Nb_(0.27)Mo_(0.26)Hf_(0.13)Ta_(0.21),which demonstrates a yield approaching 940 MPa at 1200℃ and favorable RT ductility with 17.2%fracture *** high yield strength at 1200℃ exceeds that reported for RHEAs,with 1200℃ exceeding the service temperature limit for nickel(Ni)-based *** ML-based approach makes it possible to rapidly optimize multiple properties for materials design,thus overcoming the common problems of limited data and a vast composition space in complex materials systems while satisfying multiple objectives.
Predicting the performance degradation of defective materials is a significant challenge in solid mechanics, primarily due to the oversimplification of highly irregular defects into basic shapes such as circles or str...
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Aeroelastic limit cycle oscillation results are presented for a three-degree-of-freedom plunge, pitch, and flap structural model with flap free-play in a viscous transonic flow airfoil. A nonlinear frequency domain ha...
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MagnesiumMagnesium’s remarkable stiffnessStiffness-to-weight and high strengthStrength-to-weight ratios could enable substantial vehicle lightweighting versus aluminum and steel. However, primary production is very e...
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